Project Summary: In the parent grant (R35GM131810), we proposed to study early germline development using Xenopus as a model. Specifically, we propose to study: 1) a novel mRNA translocation event essential for the activation of germ plasm during the oocyte-to-embryo transition, and 2) regulation of the first wave of primordial germ cell (PGC) proliferation by Dzip1, a novel maternal germ plasm component. Through these studies, we hope to better understand how maternal factors operate at the translational and post-translational levels to regulate early PGC development. These studies are highly relevant to human reproductive health and would make important contributions to our understanding of basic cell, reproductive, and developmental biology. The proposed studies rely heavily on healthy oocytes and embryos of Xenopus laevis. We are currently using a flow through Xenopus housing system, which was purchased in 2011. The design of the system was not optimal. As it gets old, it becomes increasingly difficult to remove biological wastes from the system. To maintain the water quality, animal care staff has to increase the frequency for water exchange and tank cleaning significantly, causing serious adverse effects on the reproductive system of the frog. This makes it increasingly difficult for us to obtain high quality oocytes and embryos, which started to delay our research progress. Here we request funds for replacing the existing frog housing system with a more modern recirculating Xenopus housing system from IWAKI Aquatic.